The number of New Zealanders moving to Australia hit a two-year low last month, Statistics New Zealand says.

Overall net migration for the month of January was 400, meaning New Zealand had more arrivals than departures.

Fewer people also departed across the Tasman during the month, with the seasonally adjusted net loss to Australia dropping to 2600, the smallest net loss since February 2011.

January's movements also arrested a run of annual migration losses since October 2011. Arrivals and departures completely cancelled out each other, giving a zero net-migration gain.

The annual net loss of migrants to Australia in January was 37,900, down from a record 40,000 in August.

The number of visitors to New Zealand fell 2 per cent in January, affected by the timing of Chinese New Year.

Some 260,600 visitors entered the country last month, and with China being New Zealand's second-biggest source of visitors, events in the Chinese calendar were starting to have an impact, Statistics New Zealand said today.

Population statistics project manager Deb Potter said that this year Chinese New Year fell in February rather than January as it did last year.

"Chinese people generally travel more around the Chinese New Year holiday, so we had fewer visitors from China and Hong Kong this January."

They were partially offset by an increase in visitors from the United States (up 3500) and Australia (up 2200).

Visitor numbers over the January-2013 year also fell 2 per cent to 2.5 million, although statisticians noted the figures were being compared with a year which included arrivals for the Rugby World Cup.